The invention relates to a dishwasher comprising a filter system for cleaning the dishwashing liquid and a method for operating the same.
During cleaning of items to be washed in a dishwasher, dishwashing residues are released from the items to washed, these accumulate in the dishwashing liquid and are partly circulated with the dishwashing liquid during the entire dishwashing process. The more dishwashing residues are entrained in the dishwashing liquid, the more disadvantageously this affects the dishwashing result. Furthermore, dishwashing residues entrained in the dishwashing liquid can become deposited in the transport paths of the dishwashing liquid or clog the sieves provided in the dishwasher.
Filter systems in the form of sieve devices which can be removed from the dishwasher, cleaned and re-inserted again have already been proposed to eliminate this problem. These sieve devices have the disadvantage that the cleaning process is laborious and unpleasant for the user. Furthermore, the cleaning process is frequently forgotten or carried out too infrequently so that problem-free operation of the dishwasher can no longer be ensured as a result of clogging of the sieve devices and hindrance in the transport paths of the dishwashing liquid, which disadvantageously impairs the dishwashing result and in extreme cases, can result in destruction of the dishwasher.
In other known dishwashing machines attempts are made to improve the dishwashing result by using large quantities of water, long running times and multistage filter systems. These dishwashing machines have the disadvantage that they have an elevated energy and water requirement. In addition, the known filter systems are not in a position to filter out fine-grained impurities in the dishwashing liquid since the sieves even of multistage filter systems are too coarse-meshed or the finer-mesh sieves impede the circulation of the dishwashing liquid in the dishwasher.